On Mon, Jun 13, 2022 at 08:11:36PM +0200, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> > > Use acpi_find_child_by_adr() to find the child matching a given bus > address instead of tb_acpi_find_port() that walks the list of children > of an ACPI device directly for this purpose and drop the latter. > > Apart from simplifying the code, this will help to eliminate the > children list head from struct acpi_device as it is redundant and it > is used in questionable ways in some places (in particular, locking is > needed for walking the list pointed to it safely, but it is often > missing). > > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> Reviewed-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx> > --- > > v1 -> v2: > * Drop tb_acpi_find_port() (Heikki, Andy). > * Change the subject accordingly > > --- > drivers/thunderbolt/acpi.c | 27 ++++----------------------- > 1 file changed, 4 insertions(+), 23 deletions(-) > > Index: linux-pm/drivers/thunderbolt/acpi.c > =================================================================== > --- linux-pm.orig/drivers/thunderbolt/acpi.c > +++ linux-pm/drivers/thunderbolt/acpi.c > @@ -301,26 +301,6 @@ static bool tb_acpi_bus_match(struct dev > return tb_is_switch(dev) || tb_is_usb4_port_device(dev); > } > > -static struct acpi_device *tb_acpi_find_port(struct acpi_device *adev, > - const struct tb_port *port) > -{ > - struct acpi_device *port_adev; > - > - if (!adev) > - return NULL; > - > - /* > - * Device routers exists under the downstream facing USB4 port > - * of the parent router. Their _ADR is always 0. > - */ > - list_for_each_entry(port_adev, &adev->children, node) { > - if (acpi_device_adr(port_adev) == port->port) > - return port_adev; > - } > - > - return NULL; > -} > - > static struct acpi_device *tb_acpi_switch_find_companion(struct tb_switch *sw) > { > struct acpi_device *adev = NULL; > @@ -331,7 +311,8 @@ static struct acpi_device *tb_acpi_switc > struct tb_port *port = tb_port_at(tb_route(sw), parent_sw); > struct acpi_device *port_adev; > > - port_adev = tb_acpi_find_port(ACPI_COMPANION(&parent_sw->dev), port); > + port_adev = acpi_find_child_by_adr(ACPI_COMPANION(&parent_sw->dev), > + port->port); > if (port_adev) > adev = acpi_find_child_device(port_adev, 0, false); > } else { > @@ -364,8 +345,8 @@ static struct acpi_device *tb_acpi_find_ > if (tb_is_switch(dev)) > return tb_acpi_switch_find_companion(tb_to_switch(dev)); > else if (tb_is_usb4_port_device(dev)) > - return tb_acpi_find_port(ACPI_COMPANION(dev->parent), > - tb_to_usb4_port_device(dev)->port); > + return acpi_find_child_by_adr(ACPI_COMPANION(dev->parent), > + tb_to_usb4_port_device(dev)->port->port); > return NULL; > } > > > -- heikki